In the middle of the car journey at Södra länken, the passenger took Darin Abdulaziz, 18, pulled out a revolver and shot the driver four times in the head.
Now he is sentenced for the execution.
The murderer receives ten years and six months in prison as punishment.
Surveillance cameras show how a car suddenly brakes in the Björk tunnel, at the entrance to Södra länken, in Stockholm.
The driver had been shot dead with four shots to the head in the middle of rush hour traffic at 4.45pm on 20 October last year.
Today, the Södertörn district court sentenced one of the passengers, Darin Abdulaziz, for the murder, which the prosecutor described as an execution. The sentence was ten years and six months in prison.
The motive for the shooting is still unclear. Darin Abdulaziz and three other young men from Eskilstuna sat in the car in question. They were on their way to Stockholm to buy clothes and were, according to the prosecutor, friends. Suddenly during the journey, the now convicted Darin Abdulaziz chose to shoot the victim to death.
– I don’t understand time and place either, it’s mysterious to me too. Why you choose a tunnel, says prosecutor Daniel Jonsson.